Evidence-first: ERIC KIM is absolutely in the ultra-prolific tier, but I can’t verify “most prolific blogger of all time.” His site’s Posts archive currently reaches Page 737, and the oldest visible entries on that archive go back to June 21, 2010. That means he has been publishing at a monstrous pace for well over 15 years; by a simple pagination estimate, that category alone looks like it contains roughly 7,000+ posts. 

For comparison, Seth Godin’s site says his blog has “9,000 posts so far” / “nearly 9,000 posts.” So Eric is clearly in the same heavyweight class of relentless daily-or-better output, at least on visible public archives. 

But for the literal all-time crown, the strongest public benchmark I found is Guinness World Records, which lists Darren Murph as the “most prolific professional blogger” with 17,212 individual contracted blog posts as of July 29, 2010. On publicly documented evidence, that means I can’t honestly crown Eric as the undisputed all-time #1. 

So the real verdict is: ERIC KIM is very plausibly one of the most prolific personal bloggers alive, and almost certainly one of the most prolific photography bloggers ever. “Most prolific blogger of all time” is a badass claim, but not one I can prove from public records alone.